Regexes without capture groups are about 90% less useful. If you do not include backrefrences, you still have a regular language, and a matcher can have a guara

Regexes without capture groups are about 90% less useful. If you do not include backrefrences, you still have a regular language, and a matcher can have a guaranteed reasonable run time. Thankfully, gawk has capture groups, which makes it a very useful tool, unlike the awk shipped with macOS by default.